The title of this book is Guns, Germs, and Steel. In Chapter 11, Jared Diamond discusses the “germs” that are referenced in the title. He argues in this chapter that farming allowed Eurasian societies to develop infectious diseases while societies in other areas did not have such diseases. When Eurasians came into contact with people like Native Americans, those diseases decimated the populations that had not been exposed to them before. In this way, farming helped Eurasians get the “germs” that helped them to dominate the world.

One piece of evidence for this claim is found in Table 11.1 on p. 207. There, Diamond shows us that many diseases that can be very deadly actually come to us from animals. Perhaps the most deadly of these diseases is smallpox. This disease is known to have killed millions of people in the Americas and elsewhere. It came to humans through their contact with livestock such as cattle.

A second piece of evidence is the fact that the populations of many places that the Europeans conquered dropped dramatically even though Europeans had not actually gotten to those places yet. We see this on p. 210 where Diamond discusses the population of Mexico. Before Europeans reached the interior of Mexico, smallpox arrived. Diamond says it was carried by an infected slave from Cuba. The disease was passed along by Mexican Indians from the coast and eventually reached the Aztec empire in the inland Valley of Mexico. Diamond says that Mexico’s population dropped from 20 million to about 1.6 million even before the Spanish got to the Aztec Empire to conquer them.

Thus, the main point of this chapter is that farmers have livestock and that livestock breeds germs. These germs help farming societies conquer other societies, thus making farming societies powerful.